Hahaha I like the cheesy melodies and upbeat tone. I know you made this in an hour and stuff, but I thought the bridge at :55 was a little bland - the very least you could do to spice it up would be to add some punchier drums to really make that solo pop. Still, the cutesy details of the piece, right down to the ritardando and plunky last note at the end, made me smile. Solid work, LE!
Also, somehow this feels a little slow-paced for Mario Kart, but maybe that's just because I always put the game on "aggressive items." >:D